Work-crimping mechanism for blindstitch sewing machines



June s, 1926. 1,588,133

C. W. MUELLER- WORK CRIMPING MECHANISM-FOR BLINDSTITCH SEWING MACHINES Filed Feb.. 14, 1924 3 Sheets-Sheet 1 17 Q1111 4 1| I u alumnus June 8;192 6. 1,588,133

C. W. MUELLER WORK CKIMPING MECHANISM FOR BLINDSTITCH SEWING MACHINES Filed Feb. 14. 1924 s Sheets-Sheet 2 gwumtoz Patented June 8, i926.

NITESDI emmnns lvrnnnnnn Oren L0'U IS, MISS'OUREQAESIGNGR "1'0 IJEWIS INVISIEBEE" srrrcrr rmcmnn cc.-, or sr; LOUIS, ivrrssounrg a conrona'rronon wonK-cmmeme men emnstcnrc n 'mctrm-Es;

Application fileil February; 14,1924. Se1'ialN0.-692,69 5.1

Thisinvention relatesto new and useful improvements. in blindrstitch sewing ma chines generally, although more. particularly to improvements. to r the. Work crlmplng or bending mechanism .such. as, for instance, as

a pocket opening...

It, is, therefore, one of theprincip'a'l ob-.-

jects-of thisinvention to provide-means for. limiting the upward crimping movement of; the, fabric, due to theinovement. of, the. plunger, and thereby maintain a predetermineddepth of needle penetration; in, the 'naaterial with relation to the upper face thereof, whereby in the operation. above. noted the. stitching will be confined tothe superimposed. layer orpocketand conse.-. 1 quently. will notpenetrate the base la-yer a'nd,

close the pocket opening.

Another object of this ,mventionis tolprovide a construction which Will avoid), the.

difficulties above enumerated, by, providing readily accessible; means for varying the depth or" theneedle penetration by limitingv the upward movement. of, reciprocation of the plunger andoperable subsequentto the initial adjustment of the plunger reciproca-v tiQn relative to the pathof the needle travel, thus, providing a sewing machine capable of,

eflicient usein many operations on garments,

such. as; the stitching of edge: tape and;

bridles on c0ats,. in. which 5 the depth of. needle penetration ,Il'lllSlizbB adjusted toallovv the.v needle to penetrate the edgetape or.

bridle and thence penetrate; or partially penetrate the canvas. lining, :but not. penetrate. the base layer, thatis v thematerialcomprising; the-outside part of the coat.

Another obj ect, ofthe inventionlies in the provision of, ajnovel plunger. adjusting mechanism which will reduceithe wearthere:

taiman. accuraterelation between-the plunger! I and the. needleg andrvvhich will. renden the adjusting. mechanism. capable :of ready;

assembly.

Other objects and features-pf the f inven tion' Will more-fully appear from the folr lowing description,- and. claims in iconj uncti'on accompany ng,- draw ngs 1n 5.

with the: which Figure 1 israypartial end: elevationof a sewing. machineembodying my invention". 3

I Figure "2 is a horizontal sectional. view taken: on the .-l1ne.2 21 ofF1gure'l. Figure. 3 1s. a vertical 'sectlonal-vievv taken on theline 3'.3 Oi Figure. 2,- theplungen v belng shown 1n its. lowermost PQSllDlOIL.

Figure 4 is a similaixviewjbut showingthe penetrating the material.

Figure 5 is anhenlargeil sectional view: of

the plunger mechanism.

Figure on. a. perspective. viewof v the:

presserefoot Figure. 7 p is a i perspective a view oi the plunger. adj usting. mechanism and r V Figure. 8. .is a. detail .sectionalr'vieW thereof.

ing'onbending theainateria'lz in; advance ofplunger i-nits highest-positionland. the-needleeach needle. penetration, the plunger being yieldably I supported relative toits actuating means: and cooperating wlthwan; opening; formed (in. a stationary presser-foot which 1s located on the upper-f side of the materials Means are provided :for; initially and bodily, adjusting the position of the reciprocatory movements of the plungercso that-the high point; of the plunger reciprocation may beinitially; located 1 a. 1, plane slightly below the'path of'the needletravel. Inord'eru-to provide means for.va-ryingthedepthi of the.

needlev penetration relative to. the upperor stitching: face of the materialuand.:Withoutdisturbing said initial adjustment of! the plunger I have provided. a vertically ad-.

justable. stop cooperating. WltllwtllB. upper face of the fabric and. located. directly above the .upper end. :of. the; plunger; Thisstop' *is carried by, a fixedpart. oi the; sewing; Ema.

chine preferably fthe presser foot, and afianeedleipenetration in the material, either during the running of the machine or while it is idle. As the stop is adjusted downwardly, the upward limitof movement of the plunger is correspondingly lessened and the material is correspondingly lowered. In

asmuch as the .needle travel is in a fixed plane relative to the horizontal, it will follow that by adjusting the stop, the depth of the needle penetration in the material will be thereby varied. Should a pocket or other superimposed fabric passunder the stop, the yieldable plunger will give way, and consequently the depth of needle penetration relative to the upper face of the superimposed fabric will remain constant. c

In the initial adjustment of the plunger mechanism it is necessary to maintain a uniform relation between the plunger and the needle and .I have, therefore, provided a novel means for initially and bodily ad- 'ustin the reci rocator. movement of the plunger, whereby the wear, on the adjust ing parts will be reduced to a minimum, and

- consequently the predetermined relation between the needle and the plunger will be maintained. This is very important,'because any wear in the plunger adjusting mecha-* nism willbecome manifest at the high point of the plunger reciprocation. This will result in the plunger moving upwardly into the path or" the needle and thereby not only damaging or destroying the needle but causing resultant stoppage to the machine with the consequent loss of time in assembling new parts and readjusting the machine.

In'carrying out my invention as shown by the accompanying drawings, thesewing machine includes the usual base 5 and overhanging head 6. The stitch forming mechanism is fully shown and described in Patent No. 1,176,415, issued to James l Vhite law, March 21, 1916, andthe work presenting mechanism is fully described in the Lewis Patent No. 1,254,818, previously referred to, and it is thought that a general description thereof will be suflicient to enable any one skilled in this art to fully understand my invention.

The work presenting mechanism includes a presser-foot 7 detachably fixed to the head 6, a 4-motion feed dog 8 operating below the material and cooperating with the pressert'oot 7 to intermittently feed the material through the machine, a vertically recipro catory plunger 9 for crimping'or bending the material in advance of each needle penetration, and a vertically reciprocatory clamp 10 for clamping the material against the presser-foot during the needle penetration.

The-pre'sser-foot 7 is provided with an opening 11 directly above the plunger 9 for permitting the latter to project the material through the opening in a ,crimped or bent formation and in a position to be penetrated by the needle 12. In this type oi machine the needle 12 is oscillated about a fixed horizontal fulcrum 13 located on the stitching head 6.

rshaft, and a link 17 'pivotally connecting the feed dogand the rockarmf The up and down movement of the feed dog is created through a rock shaft 18 havinga rock arm 19 fixed thereto, .a bell-crank120 fulcrumed on the frame at '21, a link 22 connecting the crank arm 19 to the vertical arm of the bell-crank, and a substantially vertically disposed link 23 pivotally connected at its lower end to the'horizontal arm of the bell-crank 20 and at its upper end to the feed dog 8. The work clamp 10 is supported for vertical movements by a post 24'slidabiy mounted in the frame of c the machine and is yiel-dably held in its extreme upper position by afiat spring 25 operating against the low-er end of the post.

The clamp substantially surrounds the feeddog and is pivotally supported on the post 24 by pivots 10 The plunger 9 is mounted to slide vertically within a barrel 26 which in turn is slidably mountedvertically in a guide opening 27. in the frame ofthe machine. A block2-8 is slidably mounted in the frame and is provided with'a lug 29 which extends laterally under the barrel 26. The lower end of the plunger '9 is provided with a reduced threaded end 30 which passes through a suitable opening formed in the lug 29, the reduced end forming a resultant shoulder 31. A 'coil spring 32 surrounds the reduced end30 and lies between the lug 29 and the shoulder 81, the spring tending to urge the plunger 9 upwardly into the open-.

ing 11 ot' the pressertt'oot. This upward movement of the plunger is limited by a nut 9 fixed to the lower end of the plunger and cooperating with the lug 29. It will thus be seen that when the slide block 28is moved up and-down the plunger 9 will be correspondingly moved and whenever resistance is offered to the upper movement of the plunger the spring will permit the plunger to remain stationary while the barrel con tinues its upward movement. In order to reciprocate the plunger 9, a rock-shaft 3;- 15 provided and this rock-shaft carries a r ock-arm 34 having. alink 35 pivoted as at screw 44- has threaded engagementwitht-he 1 tuating mechanism for th'eplunger,

36; teits upper end, thei other end of the.

linkage being p voted at 371101 the slide ocki28. A,

In the cyclic operation of the parts above} describechas the needle is retracted from the materiahjthelatter is moved by the feed dog a. distance of one stitch length, the plunger and thejclamp being at thistime retracted t points below and out of engagement with thematerial i The feed dog is then moveddownwardly away :Erom the material and reiturned'toits starting position of feed move-.

merit. During this return movement of the teed dog the plunger ismoved upwardly to en 'a 'e andcrim the material in the 0 en- .g; H V

ingot the presser-foot and thecla'mp is also moved upwardly t'of'clamp the material against the tootand on opposite sides of the plunger, the clamping action serving to hold the crimped material against bilateral move ment or creeping during the following needle penetration of said crimped material lVhilethe material is thus being held in its cr-imped; position, the needle penetrates the =7 sameiand the rotary hook cooperates with the needlefthreadto forma resultant stitch.

The needle is then retractedand the plunger and clampgulowered; thus completing the eyoleof operation. bo ve pointed out, 1s necesary to provide means :tor initially adjustingthe vertical positionoi'reciprocation; of the plunger rgelatiye tolthe path of needle travel and I' haveiitheretore, provided 'in the train of acan ad justable means Whereby the bodily movement I of; reciprocation of the plunger maybe vertically adjusted initially relative to. the path of needlctravel, To this end the rock 1 arm 34 is termed with an elongated opening 3 and witlra laterally extending bearing arm Fixed to the rock-shaft 33 byda set screw'40 is a holder4l'having anradially extending threaded boreq42, The bearing arm 39 or the rock arm 34 is formed, witha ball socket-43 which is disposed in alignment with the threaded borei 42. A-n adjusting bore 42, and this screw has a reduced outer end 45vior1ninga resultant shoulder 46, the. outer, end 45 passing through the ball socket 43. The reduced end 45,-of the screwis threaded} for'engagement with a ball 47 which isadapted in turn; tofbe seated in the ball socket 43. A clampingnut 48 isthreaded. onto the outer end of the reduced'end' 45 ot the screw and serves to' lock the ball 47 against movement relative to, said, adjusting.

screw. In 'order toprovide means for easily handlingand thereby adjusting the screw,

have formed, the ball 47 with an integral circular head '49 and have formed the periphery thereof, with-a seriesof notches 5 Sp.1'lng 5 1 Wl1lCl1 in thlsi-nstance is shown; '7, use .rhsliedfiatnietal spr ng 'is d sposed be;

tween the adjusting and-the crank arm; ,34,' 'tl1lS SPI-ilig being centrally f ri'nod with an opening to receive thereduced end 45 of thefscrew. Thus, the spring hasfits central portiondisposed against the shoulder 46 of the; screw andgits peripheral;portion; againstth'e bearing arm 39 ot the rock arm.

The function of this spring is; tof yieldingly maintain the ,ball in contact with itssocket, and thereby automatically takeca're of any variations between the parts due -to[wear thereof. By providing afball and socket connection, I haveprovided construction which will readily permit the assembling of the parts, although slight inaccuracies of manufacture should occur in the alignment of the bore 42 with the socket 39. In order to automatically latch the adjusting screw in anyjposition of adjustment, I have pro readily obtained bythe above described mechanisnr as it will be apparent thatuby adjusting thescrew 44 the rock arm. 34 will be moved across the axis of the-rOck-shaft 33 and the vertical position of the slide 28'wh'ich carries.the plunger will be correspondingly adjusted. It will also be noted that when this adjustment has been completed the parts. will be held against acc dental, dlspl'acement by means ot tl espring latch 52; and that any;

wear on the parts" comprisingthe' adjusting mechanism will be automatically taken upby the fiat spring51, thus avoiding any loose connections and the resultant overthrow'of the plunger relative to the path of needle reciprocation. i

From the foregoing, it will be-noted that, when the plunger mechanism is adjusted so;

that the highpoint 0t reciprocation is'located directly below tlie'patli" of needle travel the maximum needlepenetration in the material will be assured. It is,clesi1- able to vary the depth of the needle penetration'inthe material relative to the upper face thereof in order to meet the various practical requirements ofgarmentmanufacture. ,lt is des rable to provide areadily' accessible means for accomplishing this purpose either duringthe running of the machine or while it is idle, and to this end I have I provided avertically adjustable stop which is disposed above the path of plunger reciprocationand bears against vt face ofthtabric so asto variably limit the .ae upper ser-foot 7.

mg screw 59 18 provided with a head havupward' movement of "the plunger. This adjustable stop is carried by a fixed part of the sewinghead and in this particular in stance, I have positioned the stop on the presser foot 7. This stop consists oi. a lever 54 fulcrumed intermediate its ends on a horizontal pivot pin 55 which is carried by upstanding ears 56- 56 formed on the pres-- ser-toot. The lever 5% comprises an adustino' arm 57 and a work en a 'in arm' J o 7 V c: b 2::

or stop 58. ifhe lever is disposed entirely .on one side of the path of needle reciproposed directly above the path of reciprocation of the plunger.An adjusting screw 59 is threaded into the outer end of the adjusting arm 57 and bears against the pres- The upper end of this adjusting its periphery formed with a plurality of notches 61 for automatic engagement by a spring latch 62 fixed to the presser foot by a screw 63. By. turning the'screw 59 in a clock-wise direction the adjusting arm 57 ot the lever will be'moved upwardly about its fulcrum 55 and consequently the Work engaging arm or stop 58 will be lowered relative to the path of needle reciprocation, thus lowering the high point of reciprocation of the plunger and. thereby lessening the depth of needle penetration in then'iaterial; This stop will be automatically held in any position of adjustment bythe spring latch 62 cooperating with the notches, 61 of the adjusting screw 59. When it is desired to increase the depth of needle penetration in the material, the adjusting screw'59 is, of course, turned in an anticlock-wise direction, and the reverse movement of the lever 57 will be brought about.

From the foregoing it will be observed that I have provided means for bodily adjusting the position of reciprocation of the plunger preparatory to varying the high point of movement of the plunger in order to predetermine the depth of needle penetration in the material. r V

I claim 7 1.111 a blind stitch sewing machine, the combination with a, stitch forming mechanism including a reciprocatory needle operating in a constant path, of a work presenting mechanism operating below the stitch forming mechanism, a presser foot disposed above the work, a vertically reciprocatory means operating below the work material for upwardly bending the latter in advance of and for each needle penetration, and a stop adjustable vertically relatively to said presser foot and located directly above said bending means'and above said material for positively limiting the upward movement of:

said material bending means to thereby limit'the depth'of the needle penetration in V the material.

2. In a blind stitch'sewing machine, the V combination with a work presenting mechamsm, of a stitch forming mechanism including a reclprocatory needle operating 111 a constant path from a point above the work presenting mechanlsm, means for uplimit of movement of the plungerto thereby limit the depth of the needle penetration in the material, thereof.

' 3. in a blind stitch sewing machine, the combination with a work presenting mechanism, of a stitch forming mechanism in cluding a reciprocatory needle operating in a constantpath from a point above the work presenting mechanism, means for up wardly bending the work material in advance of the needle penetration including an intermittently actuated vertically movable plunger operating from below the material, a stop lever fulcrume'd above the material for positively limiting the upward movement of the plunger to thereby limit the depth of the needle penetration in the material, relative to the upper face thereof, and means for adjusting the lever on its pivot to vary the upward limit of movement of the plunger to thereby vary the depth of the needle penetration in the material relative tothe upper face thereof.

4.111 a blind stitch sewing machine, the

' combination with a work presenting mechanism including a presser foot having a "material-receiving opening, of a stitch forming mechanism lncluding a reciprocatory needle operating 1n a constant path across the opening in the foot from a point above the latter, means for bending the material into the opening of the foot in advance of each needle penetration including an intermittently actuated vertically movable plunger operating from below the material, and means above the material for positively limiting the upward movement of theplungcr to thereby limit the depth of the needle pene tration relative to the upper face of the material.

5. In a blind stitch sewing machine, the combination with a work presenting mechanism including a presser-foot having a material receiving opening, of astitch forming mechanism including a reciprocatory needle operating in a constant path across relative to the upper face the openingfi'iitheioot :Eidm a; some ebbve the latter "pies-sel foot, means for bending V the mete-rial into the opening of't'he foot.

in'advzinoe of each needle penetration incliidlng eninternnttentii aotn'ated' ve tloally V movable plunger operating .ti'oin' 'helow the material, end means above the 'ineterial' and separate fromfthe' plunger for positively limiting the upwarc'l V movement of 1 the plunger to theneby limit the depth 'ofthe needle penetration relative to the upper fate of'the material. f

6. In ablind stitch sewing machine; the combination with awon: pifesenting mechanism including a 'press'et-foot having a material-1-eceiving opening, of a stitoh formiiig mechanism including a; 'reoiprooatoiy needle "operating in constant "path across the opening the'ffoot from 23-point "above the latter, means for bendin'gthe material into the opening-of the foot in ad'vanoefof the: needle 'penetietion inclnc ling;-an interinitten'tly 'zietnat'e'd Vertically movable plunge operatingf ombelow the material, land nieensinoludin'ge Iev'ei' 'and'an a djjnstable stop therefor lo'cajte'd' 'eih'ovefthe material and separate from "the phi'nger for positively Jimitnig the upward movement of the combination of fa ,pressenfoot having at eloth opening 'a' plunge: "to Work into said cloth opening, means for feclprocatln'g sa d plniige'r toiwardsend away from said"open ing and he-Ying'a, 'yieldtt'ble connection with said plunger, and 21- ielaitively vert-i'eelly jad 'jiistafble stopinonntedhon the 'pie'sser foot to-limit the high poiit efieeip oeati n of saidplunger. s

'9. In '3 hli'nd' stiteh sewing machine, the

ooinbination of a pi'esser-fo'ot a; cloth opening, a plnnger" to work int'o 'seld cloth "openingmeans for reciprocating said plunge'r towards an away from saidopening end having a. yi'eldflole foon'nection' with said p'hingei', a stop-lever fulcr'umed on the pi'esstion of seid' plunger, and mea-ns vfor ad 'nsting saidle'ver to 'VELIY the high 'pointo'i' reoiprocation of theplungel'. V 101 In a blind stitch'sewing machine, the

. oombinatio'n'of h pressei 'foothalving-a cloth opening, fa plunger to Work into said cloth in}; and having a yieldable connection with" phmger towbli'ds {and "ditty fioinfsaid 'epee 7 ing and having a yie ldzible e'oii'neotidn Withsaid plunger, 2 stop lever "ftil'oi uined on the 'p'i'esser foot 'to limit the hi 'h point of Ire- 'i'eeipi'oc'altion of: the "plunger; and means ffoi' autom'ajtio iilly latching usti means in any positionofadjtistnient. l

d ll. .In Ea blind Stitch seWing machine, the

eonibinati'oniof a'presser' foot, having a cloth opening, a plunger to Work. into seid'cloth opening, means for reoipTooatihg said plunger towards end awa iffoin "said opening end having a y'ieldahle connection With. srid .pli'ni'ger, s stop lei er fulornnied *on the pressei footfto limit the highfpoint' of Tercipr'oottionxof "said "plunger, means for adjusting said lei ei to vary the high point of reciprocation of the plunger," said edjn'sting means comprising a screw threaded into engaging end thereof and bearih'g against the pi'esser foot.

12. In a blind stitch se'Wiii'g niajohineflthe combinition with a stitch forming meohanism including it reoiplo'oet'oi'y "needle opereti'n'g' in 'a' constant ,peth ielitiir'e to the horizontal, of a Work presenting m chanism operating "below said stitch i forming, ine'chanisin, a vertieaily i'eeipi'ooa tory 'ph'i'ngei operating belowtheLWOTkinEtei'ial foru weirdly bending said 'ma'tefial in a d ve-nce of each needle penetration, actuating'means for said plunger includin a. yieldable' om nect'ion, andfivertically adjustable lo- Gated above the material and directly above v ,the plunger for X' aria'bly limiting the extre ne npwa'i'd movement of the plunger to thereby vary the depth of theneedle penetretion in the material. 7 The oombination of a presser foot formed with an opening for receiving 'np- 'Wa rdlyprimped material;:iiidfa stop "oarriedby the foot and Vertically adjustable relatively ther'eto'foi' limiting the upward movement of the meteriel Within said open,- i'n'g, said stop being disposed above the opening of the foot.

14; The combination of a 'pressei" foot formed with anopeningfor receiving np Wardly .oTiinp'ed material, and YBI'tlOa-uy adjustable stop ca?rr ied by theffoot for limiting the n'pwerd movementof the material Within said openingysaid 'stopihcludin'g "a" lever having onee'nd disposed fabove the opening of the foot. r

'15. The combinetion of a .pre'ss'er foot formed with a openin for reo'eiving up Wardly ciinipedmateiieh a lever having 'o'ne end disposed above the opening of the foot for limiting the upward movement of the mateiiel ithin-said opening, and means'i'oi adjusting said lever "to "a; predetermined posh tion to vary the vertical position of the materialengaging end of said lever.

16. The combination of a presser foot formed with an opening for receiving upwardly crimped material, a lever having one end disposed above the opening of the foot means 'for automatically latching said admaterial within said opening, and means forl to the'end of the lever opposite the matej usting means in any position ofadj ustment.

17 The -combination of a presser foot formed with an opening for receiving upwardly crimped material, a leverhaving one end disposed above the opening of the foot for limiting the upward movement of the adjusting saidlever to a predetermined position to vary the vertical position of the material-engaging end of said lever, said adjusting means comprising a screw threaded into'the end of the lever opposite the material-engaging end thereof and bearing against the presser foot,

18. The combination of a p-resser foot formed with an opening for receiving upwardly crimped material, a lever having one end disposedabove the opening of the foot for limiting the upward movement of the material within said opening, means for adjusting said lever to a predetermined position to vary the vertical position of the material-engaging end of said lever, said adj usting means'comprising a screw threaded inrial-engaging end thereof and bearing against the presser foot, and a spring latch carried by the lever for engaging the screw to retain the latter in an adjusted position. 19. In a blind stitch sewing machine, the

combination with a, stitch forming mechanism including a reciprocatory needle operating in a constant path relative to the-horizontal, a work presenting mechanism operating below said stitch lt'ormingmechanism,

a vertically reciprocato-ry plunger operating below the work material for upwardly bending said material in advance "of each needle penetration, actuating means for said" plunger including a yieldable" connection, and a vertically adjustable stop located above the material and directlyabove the plunger for variably limiting the. extreme upwardmovement of the plunger to thereby vary the depth of the needle penetration in the material, said plunger actuating means including means for bodily varying the position of reciprocation of the plunger relative to'the pathof the needle travel.

20. In a blind stitch sewing machine, the combination with a stitch forming mecha-, DISH]; including a reciprocatory' needle operatinginaconstant path, a work presenting terial bending means tothereby limit the depth of the needle penetration in the material.

21. In a blind stitch sewing machine, the combination of a reciprocatory plunger, and means for actuating said plunger including means for bodily adjusting the position of reciprocation of the plunger, said actuating and adjusting means comprising a rockshatt, a rock-arm adjustable lengthwise across the axisof saidshaft andprovided with a ball sockethaving its axis parallel to said arm, a link connecting said plunger and said arm, and means for adjusting said rock-arm comprising a radially extending adjusting screw engageable and rockable with said shaft, a ball fixed on said screw and engageable in the socket of said rockarm, and a spring carried by the rock-arm for maintaining saidball and socket in contact.

22. In a blind stitch sewing, machine, the combination of a reciprocatory plunger, and means for actuating said plunger including reciprocation of the plunger, said actuating and adjusting means comprising a rockshaft, a rock-arm adjustable lengthwise across the axis ofsaid shaft and provided with a ball socket having its axis parallel to said arm, a link connecting said plunger and said arm, and means for adjusting said rock-arm comprising a holder fixed to said rocksshaft' and formed with a radially extending threaded bore, an adjusting screw having threaded engagement with the bore of said holder, a ball fixed on said screw and engageable in the socket of said rock-arm, and a spring carried by the'rock-arm for maintaining said ball and socket in contact.

23. In a blind stitch sewing machine, the combination of a ,reciprocatory' plunger, and

means for actuating said plunger including means "for bodily adjusting the position of reciprocation of the plunger, said'actuating and adjusting means comprising a rockshaft, a rock-arm' adjustable lengthwise across the axis of said shaft and provided with a ball socket having its axis parallel means for bodily adjusting the position of "m ball fixed to the reduced outer ;end of said screw and engageable in the ball socket of said rock-arm, and a spring interposed be tween the shoulder of the screw and the rock-arm for maintaining said ball and socket incontact. r V

24:; In a blind stitch sewing machine, the

combination of a reciprocatory plunger, and

means for actuating said plunger including means for bodily adjusting the position of reciprocation of the plunger, said actuating and adjusting 'means comprising: a rock-' shaft, a rock-arm adjustable lengthwise across'the axis of said shaft and provided with a laterally extending bearingarm having a ball-socket formed therein, the axis means for bodily adjusting the position of reciprocation of the plunger, said actuating and ad usting means comprising .a rockshaft, a rock-arm' adjustable lengthwise across the axis of said shaft and provided with a ball socket having its axis parallel to said arm, a link connecting said plunger and said arm, and means for adjusting said rockarm comprising a radially extending adjusting screw engageable and rockable with said shaft, a ball fixedon said screw and engageable in the socket of said rock-arm, a spring carried by the rock-arm formaintaining said ball and socket in contact, and means for latching the screw in any position of adjustment. v

' 26. In a blind stitch sewing machine, the combination of a reciprocatory plunger, and means for actuating said plunger including means for bodily'adjusting the position of reciprocation of the plunger, said actuating and adjusting means comprising a rockshaft, a rock-arm adjustable lengthwise across the axis of said shaft and provided with a. ball socket having its axis parallel to said-- arm, alink connecting said plunger and said arm, and means for adjusting said rock-arm comprising a radially extending adjusting screw engage'able; and rookable with' said shaft, a ball'fixed on said screw and engageable in the socket of saidrockarm, a spring carried by the, rock-arm for maintaining said ball and socket in contact, and a spring latch carried bythe rock-arm and (co-operating with the screw to retain the latter in an: -position of ad'ustment.

27. In a blind stitch sewing machine, the combination with a stitch forming mechanism including a reciprocatory needle opcrating in a constant path, awork presenting mechanism operating below said stitch forming mechanism, a vertically reciprocatory means operating below the Work material for upwardly bending the latter in advance of and for each needle penetration, a stop located; above said material and directly' above said bending means, and means for vertically adjusting said stop during the run ning of the machine for positively limiting the upward movement of said material bending means to thereby limit the depth of the needle penetration in the material.

28.'In a blind stitchsewing machine, the combination with a stitch forming mechanism including a reciprocatory needle operating in aconstant path, a work presentinginechanism operating below said stitch forming mechanism, a vertically reciprocatory means operating below the work material for upwardly bending the latterin advance of and. for each needle penetration, a stoplocate'dabove said material at one side of the path of the needlereciprocation and directly above said bending means, and means forvertically adjusting said stop during the running of themachine for positively limiting the upward movement of said material bending means to thereby limit the depthof the needle penetration in the material.

In testimony whereof I hereunto affix my 7 signature.

, CHARLES W. MUELLER; 

